1. Field
The invention relates to a dynamic bone anchor. The dynamic bone anchor comprises a longitudinal core member and a plurality of tubular segments provided on the core member. In a first configuration, there is a distance between the tubular segments in the longitudinal direction and the tubular segments are movable relative to one another. When the bone anchor is in the first configuration, the core member can perform small movements transverse to a longitudinal axis. In an optional second configuration, the tubular segments abut against each other and cannot move. The dynamic bone anchor can be used in any kind of bone fixation or stabilization device, such as pedicle screws or bone plates, for the purpose of allowing a limited motion of components of the device.
2. Description of the Related Art
A dynamic bone fixation element is known from US 2009/0157123 AI. The dynamic bone fixation element includes a bone engaging component and a load carrier engaging component. The bone engaging component includes a plurality of threads for engaging a patient's bone, and a lumen. The load carrier has a shaft portion that at least partially extends into the lumen. A distal end of the shaft portion is coupled to the lumen, and at least a portion of an outer surface of the shaft portion is spaced away from at least a portion of an inner surface of the lumen via a gap, such that the head portion can move with respect to the bone engaging component.